Orifice structure in apparatus for extruding molten metals

ABSTRACT

AN IMPROVED ORFICE STRUCTURE IS PROVIDED IN AN APPARATUS FOR RXTRUDING FINE DIAMETER WIRE. IN THE PRIOR PRACTICE, REPEATED ORFICE FAILURE IN SUCH APPARATUS HAD BEEN EXPERIENCED WHEN EXTRUDING STEEL CONTAINING MELTS, SUCH AS ALLOYS OF STEEL AND ALUMINUM, WHICH MUST BE PROCESSED AT TEMPERATURE IN EXCESS OOF 1500* C. THE CAUSE OF SUCH FAILURE WAS LARGELY DUE TO AN SUFFICIENT HIGH TEM-   PERATURE STRENGHT OF THE CERAMIC MATERIAL FROM WHICH THE ORFICE STRUCTURE WAS CONSTITUTED. IT HAS NOW BEEN FOUND THAT THIS PROBLEM IS OVERCOME WHEN THE ORFICE DEFINING ELEMENT CONSISTS OF A HOT-PRESSED BERYLLIUM OXIDE CERAMIC HAVING A DENSITY OF FROM 2.9 GM./CM.3 TO 3.0 GM./CM.3

DEFENSIVE PUBLICATION UNITED STATES PATENT OFFICE Published at therequest of the applicant or owner in accordance with the Notice of Dec.16, 1969, 869 O.G. 687. The abstracts of Defensive Publicationapplications are identified by distinctly numbered series and arearranged chronologically. The heading of each abstract indicates thenumber of pages of specification, including claims and sheets ofdrawings contained in the application as originally filed. The files ofthese applications are available to the public for inspection andreproduction may be purchased for 30 cents a sheet.

Defensive Publication applications have not been examined as to themerits of alleged invention. The Patent Oflice makes no assertion as tothe novelty of the disclosed subject matter.

PUBLISHED MAY 7, 1974 T922,004 ORIFICE STRUCTURE IN APPARATUS FOREXTRUDING MQLTEN METALS Jerome J. English, Cary, and Nicholas K. Harakasand Bernhard T. Junker, Raleigh, N.C., assignors to Monsanto Company,St. Louis, Mo.

Filed Nov. 1, 1973, Ser. No. 412,370 Int. Cl. 322d 11/00 US. Cl. 16482 1Sheet Drawing. 10 Pages Specification An improved orifice structure isprovided in an apparatus for extruding fine diameter wire. In the priorpractice, repeated orifice failure in such apparatus had beenexperienced when extruding steel containing melts, such as alloys ofsteel and aluminum, which must be processed at temperatures in excess of1500 C. The cause of such failure was largely due to an insufficienthigh temperature strength of the ceramic material from which the orificestructure was constituted. It has now been found that this problem isovercome when the orifice defining clement consists of a hot-pressedberyllium oxide ceramic having a density of from 2.9 gm./cm. to 3.0gm/cm.

May '7, 1974 J. J. ENGLISH ETAL 'T922,004

ORIFICE STRUCTURE IN APPARATUS FOR EXTRUDTNG MOLTEN METALS Filed Nov.

